Ionographic film processor and associated method

ABSTRACT

A processing apparatus for the development and associated manipulation of image record media (cassettes) having latent electrostatic images formed on an insulative film removably attached to the medium. The apparatus embodiment comprises a plurality of successive stations including an initial &#39;&#39;&#39;&#39;entry station&#39;&#39;&#39;&#39; where the &#39;&#39;&#39;&#39;record&#39;&#39;&#39;&#39; (i.e. an imaging plate including the image film and associated rigid support means) is automatically separated from the rest of the cassette; an automatic &#39;&#39;&#39;&#39;toning station&#39;&#39;&#39;&#39; with associated record positioning means adapted to bring the record into operative relation with toner delivery means and to automatically deliver an appropriate portion of toner uniformly to the film surface; a &#39;&#39;&#39;&#39;fixing station&#39;&#39;&#39;&#39; whereat the image, so toned and developed, is fixed upon the record film; and transport means for automatically advancing the record from one station to the next in a prescribed controlled, repeatable manner. The particular embodiments shown are especially adapted for handling ionographic cassettes of the &#39;&#39;&#39;&#39;prepackaged&#39;&#39;&#39;&#39; type.

United States Patent 1191 Baker et al.

1451 Nov. 18, 1975 IONOGRAPHIC FILM PROCESSOR AND ASSOCIATED METHOD [75] Inventors: Joseph R. Baker; William W.

Busche; Sidney E. Hindell, all of San Diego, Calif.

[73] Assignee: Diagnostic Instruments, Inc., San

Diego, Calif.

[22] Filed: Mar. 18, 1974 [21 Appl. No.: 452,070

Related US. Application Data [63] Continuation of Ser. No. 300,311, Oct. 24. 1972,

abandoned.

[52] US. Cl. 250/315; 250/468; 250/470 [51] Int. Cl G03g 15/00 [58] Field of Search 250/315, 315 A, 468, 469, 250/470 [56] References Cited UNITED STATES PATENTS 2,711,481 6/1955 Phillips 250/315 3,057,997 10/1962 Kappelian 250/315 3,390,634 7/1968 Ver Derber 250/315 3,650,620 3/1972 Hoyt 250/315 3,672,760 6/1972 Lunning et a1 250/315 FOREIGN PATENTS OR APPLICATIONS 8/1970 Germany 250/318 Primary Examinerlames W. Lawrence Assistant Examiner-B. C. Anderson [5 7 ABSTRACT A processing apparatus for the development and associated manipulation of image record media (cassettes) having latent electrostatic images formed on an insulative film removably attached to the medium. The apparatus embodiment comprises a plurality of succes-,

Sive stations including an initial entry Station" where the record (i.e. an imaging plate including the image film and associated rigid support means) is automatically separated from the rest of the cassette; an automatic toning station with associated record positioning means adapted to bring the record into operative relation with toner delivery means and to automatically deliver an appropriate portion of toner uniformly to the film surface; a fixing station whereat the image, so toned and developed, is fixed upon the record film; and transport means for automatically advancing the record from one station to the next in a prescribed controlled, repeatable manner. The particular embodiments shown are especially adapted for handling ionographic cassettes of the prepackaged type.

15 Claims, 30 Drawing Figures U.S. Patent Nov. 18, 1975 Sheet1of14 3,920,991

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Durbmm n N0 w P mm A BACKGROUND OF THE INVENTION This invention relates to apparatus and related methods for automatically manipulating unit record media,

advancing them through a series of stations; and particularly to applications of such apparatus for the handling of image records bearing latent electrostatic charge images. I

More specifically, this invention relates to improved cassette-handling mechanisms for advancing cassette units seriatim past various automatic treatment stations such as those adapted for unwrapping and (at least partially) disassembling the cassette to extract the image record; for applying toner particles and then projecting fixing radiation to this record and for ejecting the treated record for further use; while storing the other, (non-image) portions of the cassette. Such mechanisms are described and illustrated as especially adapted for Ionogram Cassettes. 1

BACKGROUND ART The phenomenon known as lonography and its underlyingprinciples have been known for some time and involvethe generation and development of X-ray images utilizing photoemissive sourcemeans and electrostatic image media, as opposed to silver halide film media commonly used at present for X-ray imaging. Xeroradiography is similar, but involves photoconductive, rather. than photoemissive, imaging means. A

primitive version of the basic ionographicprocess was disclosed by .Chester Carlson in US. -Pat. No. 2,221,776; later, by E. L. Criscuolo in NAVORD Report 4033, dated July 6, 1955, and in related U.S. Pat. No. 2,900,515 issued Aug. 18, 1959. An article by R. A. Youshaw and J. A. Holloway inNon-Destructive ,Testing, Volume.l7, September-Octoberv 1959, page 297, and another by K. HnReiss in Z. Angew Physik,

1965, Volume 19, page 1, gave further initial details.

' The Basic Process graphic anode is disposed between the X-ray sourceand the working gap it is made relatively.radio-transparent and has affixed to it an image-receiving dielectric receptor sheet. This sheet faces the working gap and is adapted to receive and retain electrostatic charge patterns corresponding to the incident X-radiation pattern. The receptor sheet may comprise a thin plastic film (e.g. Mylar by du Pont) or the like and will exhibit good charge-retaining,dielectric, properties.

The cathode, on the other hand,-is adapted to support a photoemitter layer confronting this receptor sheet across the working gap, and is adapted to generate charged particles (electrons, ions) in direct proportion to the amount (and kind) of incident X-radiation, and in this manner, project onto the receptor sheet an electrostatic charge-image corresponding to the pattern of incident radiation. This photoemitter may comprise a thin film of lead, lead oxide, or other efficient absorber of X-radiation (see the aforementioned Reiss reference where lead and like heavy metals are designated). The receptor sheet and photoemitter are thus separated by a prescribed fixed distance defining this working gap," with the X-ray subject being disposed outside, preferably on the anode side. A quenching gas may be provided in the gap; in some instances being flowed therethrough.

As workers in the art well know, when a subject is disposed adjacent this anode and the radiation (usually X-ray photons; although gamma ray photons may, at times, be feasible), is projected into the subject, being differentially absorbed thereby, the amount of flux passing through the subject, and not absorbed, is inversely related to the amount and kind of mass through which it must pass. The emergent radiation pattern,

thus representing a sort of shadow image of the subjects cross-sectional mass, is then passed through the relatively transparent anode and associated receptor sheet to cross the working gap and strike the photoemitter surface where it is intended to be substantially absorbed. in response, the photoemitter is designed to eject electrons having energies up to the kilo-electron volt level, with the number of electrons from any given area being a function of:

(l) the number of X-ray photons absorbed there, (2) the depth of absorption, and (3) the incident photon energy.

Upon ejection from the photoemitter, the electrons traverse the gap, being attracted toward the anode by the DC field. Any quenching gas resident in the gap decelerates the passing electrons, reducing their tendency to scatter upon impacting the receptor sheet and also increases the number of electrons through secondary ionization. The electrons, plus any negative ions which may be generated in the gap (by attachment to components of the quenching gas) are collected at the receptor as a charge-image. The overall pattern of deposited electrostatic charge (latent electrostatic image), thus comprises an array of negative charges indicating the radio-transparency of (overlying portions of) the irradiated subject, with a relatively high charge density from areas which are more radio-transparent and less charge beneath areas which are more radio-opaque.

This latent charge image may then be made visible by development techniques well understood in'the art, or at times by known cathode ray tube display techniques.

Described and illustrated herein are ionographic cassettes embodying the aforedescribed anode/receptor sheet and cathode/photoemitter combination with intermediate working gap; the overall combination being here characterized as an ionographic record assembly or cassette." The preferred embodiment of the subject invention will concern apparatus for manipulating,

developing and otherwise handling such cassettes.

Problems Objects Following the discovery of the basic ionographic concepts a variety of methods and associated machines and devices have been proposed at various times to place lonography on a more widespread, efficient, faster and more commercial basis. For the most part, such devices have been quite limited in concept and intended only to handle narrow, specialized problems and, have lacked the versatility and widespread applicability necessary for putting ionography to use on a broad commercial basis. Although certain of these machines and devices are contemplated for relatively wide application, none can be considered to be really practical for a wide variety of ionography applications. For example, prior art machines (eg for similarly handling conventional film or Xeroradiograms) have been limited in the type and size of image records they can handle or in the manner and efficiency of record assembly and disassembly or in handling speeds (for both imaging and development). Associated with such limitations, of course, are related considerations of efficiency, speed, cost-control and reliability.

It is therefore an object of this invention to improve electrostatic record handling apparatus, and associated methods, so as to better implement and control the handling and manipulation of such records, especially for image development.

It is a further object to apply such apparatus to the development and fixing of images on ionographic media.

It is yet a further object to adapt such apparatus to pre-packaged ionographic cassettes.

It is yet a further object to adapt such apparatus for automatically transporting and otherwise manipulating such cassettes and automatically advancing them through treatment stations adapted to prepare, develop and fix the record media.

It is a further and related object to apply such apparatus for such manipulation including the preparatory opening and disassembly of such cassettes in a controlled automatic fashion.

It is yet another object to also provide for the automatic, controlled separation of receptor film from such cassettes, as well as for the storage of the remaining cassette portions for salvage, reuse, etc.

These and other objects of the invention will become more evident through consideration of the following disclosure and illustrative drawings wherein preferred embodiments are indicated, comprising in brief, an ionographic cassette development machine including entry means for accepting the cassette and performing unwrapping and image-record separating operations thereon; means for applying toner to the image record in a rapid, controlled automatic manner; means for fixing the so-developed image; and means for automatically advancing the image portions from one such treatment station to the next and ejecting it in a prescribed, efficient, controlled manner.

For a better understanding of the invention, as well as other objects and further features thereof, reference is invited to the following detailed description of the invention, especially its preferred embodiment, to be read in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts comprising:

FIG. 1 is a top perspective view of an ionographic cassette assembly illustrative of record units adapted for handling by the apparatus to be described; and

FIG. 2 is schematic, fragmentary, sectional view of this cassette, with members enlarged and explodedapart for clarity;

FIG. 3 is a very schematic, upper perspective of such a cassette in position at each of the different stations of the apparatus to be described; the illustrated condition of the cassette at each station and the schematic indication of various operating members being intended as a guide and overview to the successive cassette manipulations undertaken by the subject apparatus;

FIGS. 4 and 5 are upper-left and upper-right perspective views, respectively, of the preferred embodiment. of a cassette handling Film Processor to be described;

FIGS. 6, 7 and 7A are, respectively, a plan view, a front fragmentary elevation and an enlarged side-elevation, of the cassette entry station of the machine in FIGS. 4 and 5; with FIGS. 8 and 9 showing an enlarged fragmentary elevation and plan views, respectively, of the envelope-slitting elements of this station; while FIG. 9A indicates the cutter bar and knife elements of FIG. 9 exploded-apart for clarity;

FIG. 10 is a rather schematic functional showing of the transport elements of the foregoing machine shown in conjunction with cooperating driving and positioning members, together with illustrative ionogram record units being shown at successive treatment stations (after the manner of FIG. 3); these illustrative units being shown in plan view in FIG. 11;

FIGS. 12 and 13 are enlarged elevational side and end views respectively of one of the driving pawl elements of the transport assembly indicated in FIG. 10; while FIGS. 14 and 15 are elevational side and end views respectively of an envelope-slitting member of the same transport assembly; with FIG. 16 showing the pawl of FIG. 13 in conjunction with other portions of the chain loop and associated supporting and guiding members in operative relation with an illustrative ionogram record;

FIGS. 17 and 18 are plan and partly-sectional side elevation views respectively of the development station of the apparatus of FIGS. 4 and 5; with FIG. 19 indicating a somewhat simplified and differently sectioned end view of the elements in FIG. 18 and FIG. 19A showing an enlarged portion of FIG. 19; FIGS. l8, 19 also indicate illustrative cam actuation elements of this assembly as adapted to depress and raise the cassette during development as well as manipulate associated controls, these elements being indicated in perspective view and exploded away from one another for clarity;

FIG. 20, indicating in side-section, the toner powder delivery assembly operating in conjunction with the elements for this treatment station, these also being indicated in a somewhat simplified fragmentary schematic plan view, in FIG. 20-13, with a nozzle portion thereof indicated in enlarged front elevation in FIG. 20-A;

FIGS. 21 and 22 are plan and side elevational views, (FIG. 22 in partial section) of the fusing station portion of the apparatus indicated in FIGS. 4 and 5; with FIG.

2l-A indicating the reflector of these figures in upper perspective;

FIG. 23 is a Timing Chart showing salient cassette treatment steps in conjunction with the operative state of some'of the principal electrical and mechanical elements of the assembly; and

FIG. 24 is a schematic circuit diagram of the various electrical driving elements and associated switching and control elements for the machine of FIGS. 4 and 5.

Illustrative Cassette As stated above, the invention has special advantages and utility when used in connection with a prescribed prepackaged arrangement of ionographic electrodes and associated elements, i.e. an ionographic cassette, although other rigid image record media may be similarly handled. A particular example is the cassette 111 illustrated in FIGS. 1 and 2, and for which the preferred handling apparatus embodiments later described are especially adapted, although workers in the art will understand that other cassettes may be used. Cassette 111 will be seen to comprise a multi-layered sandwich of electrodes, etc. enclosed in an outer, gas-tight envelope 113 having a connector assembly 115 through which the electrical (exposure) potential and the gap medium (gas; see terminals 115-a, -b) are to be supplied. Cassette 111 is more fully described in copending, commonly assigned US. Pat. Application Ser. No. 264,247, entitled Cassette Unit," by Sidney E. Hindell filed on June 19, 1972 (herewith incorporated by reference).

Cassette envelope 113 preferably comprises a pliable, heat-shrinkable polymer film material, heatsealed along one edge 117, being perforated to admit terminals l-A, -B. Within envelope 113 are the basic ionographic imaging elements including an anode (receptor) assembly R and cathode(emitter) assembly E. Anode assembly R comprises a substrate plate 119 (preferably phenolic) providing a flat substrate on the lower face R-l of which there is, a hold-down" film 131 (discussed below) and (removably) affixed thereon, an image sheet, or receptor, 133 for receiving the charge-image. Although plate 119 may comprise a suitably flat, stiff radio opaque metal (e.g. Berylium has been found suitable, properly treated for flatness),

where, as here, it comprises a nonconductor, it must be provided with a suitable conductive anode surface (on R-l) here provided by aluminum foil 121 or the like. A metal tab 123 is provided for electrical interconnection between anode surface 121 and other elements.

Disposed opposite anode surface 121 and receptor 133 thereon, and in spaced, parallel relationship there with (see spacer 129), is the cathode assembly E comprising conductive cathode substrate 125 (e.g. aluminum), having a photoemissive layer (emitter) 127, preferably comprised of lead oxide. Emitter coating 127 is laid down as substrate 125 and adapted to emit electrons responsive to X-radiation incident thereon, as known in the art. The gap distance and the parallel relationship (between the receptor film 133 and emitter 127) are maintained by an intermediate spacer 129, formed to be coextensive with the peripheral margins able adhesive material, preferably comprising a compliant vinyl material such as Blue Vinyl supplied by Tilley Manufacturing Co. of San Carlos, Calif. or other such known adhesive backing. Vinyl hold-down 131 is abutted very flat against conductive anode surface 121,

completely covering it and adhering thereto. Then, the

insulative receptor-133 may be affixed flat upon the adhesive face of hold-down 131 to become affixed removj ably thereto; to lie flat in parallel, equidistant relation with anode surface 121 and spaced equidistant from planar cathode plate 125 a prescribed gap distance.

Film 1'33 is intended to be removed, manually, from hold-down 131 after the development of the latent electrostatic image (see below).

The charge image formed during the ionographic process must be deposited on receptor 133, which,

6 thus, preferably comprises a polymeric dielectric film (e.g. Mylar by du Pont).

Anode has two gas ports 137 (only one shown) which communicate with respective openings 139 (only one shown), in photoemissive layer 127 adjacent the edge, thereof. Ports 137 admit gas into the gap area, between receptor 133 and emitter 127, communicating from outside through terminal tubes 115.

In assembling cassette 111, substrate 133 is first secured on flat anode surface 121 (of substrate 119) by holddown layer 131. Spacer 129 is bonded to the cathode 125 (actually to emitter 127 there) with a suitable adhesive and portion 141 of connector 115, which includes a front surface and a rear surface, is then attached to cathode plate 125. The connector fittings may be secured to one or both of the electrode surfaces for delivering electrical power thereto. The gas-tight envelope 113 may then be applied to enclose the cassette elements, functioning not only to seal out contaminants and seal in the gas but also to retain the entire assembly, maintaining the gap spacing between active electrode surfaces.

Workers in the art will appreciate that a cassette like the foregoing is advantageous for use in ionographic or related electro-photographic processes. Not only are the component elements unique and useful in themselves; but they are packaged and arranged for efficient, convenient assembly and disassembly (e.g. after the charge image on receptor 133 has been developed). For instance, cassette 111 provides a unit wherein the active (emitter, receptor) ionographic elements can be prealigned and assembled into a compact, readily-usable package, very conveniently; wherein the electrodes can be easily spaced from one another, and from the receptor film, using precise automatic equipment; wherein a quenching gas can be readily injected and maintained in the working gap; and wherein the receptor and its backing (rigid anode plate) can readily be manipulated (e.g. transported and positioned) with high speed, precise automatic equipment as specifically described below.

Cassette 111 thus facilitates production of ionographic images quickly and in rapid succession, since the cassette elements are preassembled and ready for use, requiring only a connection with a suitable power source/control unit. This cassette facilitates automatic disassembly (e.g. along cleavage-plane CP) whereby envelope 113 may be readily cut (preferably below plane CP so plate R may slide laterally under, rather than over, the cut edge of the envelope, thus protecting film surface 33-8 and leaving the latent (charge) image thereon undisturbed. Envelope 113 may be strippedaway, along with the cathode-spacer assembly, leaving the receptor/backing anode unit (anode plate R) to be further manipulated automatically (e.g. for development and fixing), without requiring manual interven- -tion and its associated costs, potential for error, etc.

Thereafter, the receptor may be readily removed from the anode backing for further treatment and use. Such a cassette thus provides for the salvage and reuse of all elements save the shrink package 113- and the receptor film but the latter may serve as its own print (positive or negative; e.g. transparencies). The invention, as detailed below, is directed toward providing equipment for automatically performing such manipulations on a cassette like this.

Processor Embodiment; Overview of Functions Of course, this invention is principally concerned with manipulating discrete rigid electrostatic image media, such as ionographic cassettes, flat image film strips or sheets. or the like. Specifically. the principal embodiment herein concerns development apparatus for such media wherein individual record units, such as cassette 111, may be inserted into a machine for automatic disassembly, automatic advancement to successive development and fixing stations (and to related stations), to be, there, treated automatically, all under a prescribed program with precise machine control and requiring no operator intervention.

Referring now to the drawings, there is shown. in FIGS. 4 and 5, an Ionographic Cassette Processor" 1 (development machine embodiment) for developing electrostatic (e.g. ionographic), image patterns from discrete ionographic cassette type media of the type aforedescribed. Such media will be assumed to have been exposed in a prescribed manner to form the electrostatic image on its receptor; for instance, this being automatically effected using a prescribed mobile Exposure Console of the type described in copending, commonly assigned patent application Ser. No. 392,095, entitled Ionographic Exposure Method Apparatus filed Aug. 27. I973.

The overall general machine organization and functions will now be described. referring also to FIG. 3 where a sample cassette is depicted as undergoing various salient manipulations by this machine. These are indicated here in a rather functional fashion (the particular implementing electrical and mechanical parts being shown and described elsewhere). Processor 1 has been intentionally designed, according to a feature of novelty, to both house the parts required in developing cassette film of the type described above, as well as to provide an attractive machine package which may be compatible for the typical user environment (e.g. office, clinic, hospital or laboratory) contemplated for generating and developing ionographic images and related operations.

The machine elements have been packaged in a relatively simple, compact, aesthetically-pleasing configuration with convenient modular dimensions (e.g. this embodiment being roughly 4 feet long by 3 feet high by slightly more than 1 foot deep). The machine includes a relatively flat top working surface with a removable hinged cover 2, conventional outer covering skins and access doors, plus a set of roller wheels 3 to make it movable. Supply and storage elements (e.g. Emitter bin 21, Receptor bin 71, air pump 85, Fuser Power Supply 81, Control Unit 83) are mounted for reasonably good access and servicing on a machine frame, based on a bed 5, most being accessible from the front, with few elements hidden." Other, more active machine elements (e.g. inject drawer 31, Developer Chamber 50, Toner reservoir 51, fuser assembly 60 and associated elements, including Transport assembly 90 see FIG. 5 are suspended at the top of the machine for optimum operator access, monitoring, servicing of moving parts and sensitive items" etc.

All equipment is adapted for conventional power sources (115 VAC, 60 Hertz; requiring a maximum of about 5 amps) with no plug-ins being necessary, such as for air, auxiliary power, pressurized gas, water, etc. As detailed below, the packaging is even arranged to store "discarded cassette elements, i.e. those not serving as the image record. In summary. the user need only roll this Processor into his lab, plug it into a conventional power line and switch-on the power interlock to prepare" for use. Then, by his merely inserting a Cassettte onto the inject-drawer. a full series of controlled development steps will be quickly (order of a minute) and automatically performed without his intervention and a finished ionogram delivered (eject slot 8) for his immediate use. Workers in the X-ray imaging arts will welcome such quick, easy, automatically controlled processing. and recognize what a step forward it constitutes over present day techniques with film or xeroradiograms.

Details of Processor 1 will be particularized later, but its general overall configuration will first be summedup as follows: The treatment elements may be grouped into an Entry Station I, a Development Station II, a Fixing Station Ill and an Eject Station IV.

More particularly, the Entry Station I includes a cas sette-holding drawer 31 into which cassettes of prescribed dimensions are inserted, being thereby prepositioned in prescribed alignment with cutting and transport means, so that when drawer is pushed (fully) into the machine, automatic development of the cas; sette will begin, starting with automatic slitting of the envelope. The envelope is side-slit as the drawer is injected; then top-slit, so that a transport mechanism can automatically remove the receptor plate from its cassette assembly and advance it to the Development Station.

Development begins automatically when the plate reaches Development Station II, i.e. the plate is then lowered onto a powder cloud developer chamber where an aerosol cloud of toner dust is automatically injected and applied to the plate in a carefully controlled manner; this sequence being automatically terminated and the plate returned to the main advancement path when development (timed) is complete.

The plate is next advanced downstream to the fusing (fixing) Station III, where a fuser unit is energized to project a prescribed toner-fusing radiation fixing the powder on the receptor plate on the fly.

Lastly, the plate is ejected at Ejection Station IV (slot 8) so as to be available for manual withdrawal. Here, the developed plate may, at the operators pleasure, be manually removed and the image-film stripped from its anode backing plate to be used this removal automatically enabling the machine for its next plate.

Workers in the art will readily appreciate that the foregoing arrangement and features of novelty for cassette handling are surprisingly well adapted for operator convenience and for efficient servicing and monitoring of sensitive parts, while yet employing means which are relatively simple, incomplicated and reliable. For instance, the moving mechanical parts for advancing, cutting, developing and otherwise manipulating the cassette plates are very thoughtfully located at the very top of the machine (and unobstructed), at approximately "torso level," for convenient operator access, monitoring and intervention as necessary. In particular, the chain-driven plate transport is simple and compact in design and is located atop the other manipulative elements to be eminently handy for adjustments and servicing; yet it doesn't block observation of, or access to, the other means. The machine is also preferably provided with a lid 2 (shown only in FIG. 4) which is hinge-mounted and arranged to cover the top of the machine and isolate the inner elements (e.g. for safety,

muffling of noise and heat etc.). A convenient array of torso-level working surfaces are also thus provided, whether the lid is up or down.

Turning more particularly to FIG. 3, the aforedescribed treatment station I through IV (injection, development, fixing and ejection, respectively) will, here, be rather functionally indicated in terms of the disposition and condition of a sample cassette plate as it progresses through each station. More particularly, at Entry Station I there is shown an illustrative cassette unit 111, to be understood as having already been inserted in proper alignment into the drawer 31 (when the drawer was retracted, fully, out of machine 1 as in FIG. 5); with the drawer, then, being pushed fully into the machine, so as to thrust the cassette between a pair of opposed rotary knife assemblies EC, adapted to slit the sides of envelope 113 as aforesaid (such a slit being indicated by the dotted line SL SL along the sides of cathode plate 125 in FIG. 2). These knives are more particularly described below (FIGS, 7-9) but may be generally understood, according to this side-slitting feature as engaging the (aluminum) cathode base plate 125 (see FIGS. 7, 8) just below the cassette cleavage plane (CP, FIG. 2) and wiping the envelope along the sides of plate 125 to thereby sever or otherwise rupture it just below plane CP, in both sides.

A second envelope-cutting action is nextinitiated, according to a top-slitting feature, being indicated, rather functionally, at station I as to be performed by a top-cutting blade TCB, here understood as having partially slit envelope 113 across its top midsection, transversely to the side-slits.

This top-slitting is quickly followed by a plateadvance" sequence whereby a pushing pawl pp, is presented to engage the upper position of cassette 111 (i.e. receptor plate R) laterally, (Transverse to inject direction) from Station I toward Development Station II along appropriate guideways, this advancement being indicated in FIG. 3 as partly completed. Pawl pp is carried on, and driven by, a chain drive means (DCI-I here). Receptor imaging plate R will be understood as comprising anode base plate 123 together with imaging receptor film 133 and intermediate adhesive backing layer 131. This advancement will, of course, serve to separate receptor plate R from the rest of cassette 111 (at cleavage-plane CP) and push R to the right, see FIG. 7) with its right edge pushing out under the depending side-flaps of envelope 113, over spacer 129 to engage guideways T-g. Guideways T-g (see also FIG.

11) include an upward-canted leading-edge (left lip of base) so that plate.R is' immediately lifted up: away from the spacer 129, lest 129 interfere with the imaging surface (side-slitting above plane CP would allow these flaps to wipe image surface 33-8 and might even damage the film 133).

Removal of plate R leaves the rest of the cassette assembly (emitter portion within the non-slit E in envelope l13) in place on drawer 31 at station I. When drawer 31 is next retracted again to the full-out position (FIG. 5 means are provided according to an.

emitter storage feature, to drop this assembly into storage. That is, stop means (edges 33-E on cutters EC) hold the discard emitter IN, while drawer 31 slides out from under, and allow it to drop into emitter storage bin 21 (onto platform 34 thereof). As detailed later, this disposition of the lower cassette portion takes place somewhat later in the treatment cycle; however,

it is suggested as an accomplished fact in FIG. 3 by its 10 disposition on lift platform 34 (note from above that emitter E comprises cathode plate 125, with attached photoemitter 127 and superposed spacer 129, together with connector unit 115, all being enclosed here in slitenvelope 113).

Receptor plate R is continually advanced until it reaches Development Station II, at which point the advancing mechanism is temporarily halted and according to a toning elevator" feature plate R is then automatically lowered onto a toning chamber TC (or 51, FIG. 10) and later is raised again to resume advancement. That is, the toning elevator means is adapted according to this feature, to lower the plate into engagement with a powder cloud unit (functionally indicated in phantom as chamber TC) where the toner will be delivered uniformly to the image surface 133-8 for development of the latent electrostatic image pattern there. After development, this means automatically raises the plate back up to resume engagement with its advancing pawl pp. According to a further, related toner delivery feature, this toner cloud is automatically generated, delivered and suppressed, synchronous with the indicated movement of the receptor plate, the composition of this cloud and its manner of delivery being carefully repeatably controlled.

Pawl pp now resumes its progress, advancing plate R toward the next downstream treatment station, Fixer Station III. According to another flash-fixing feature of this invention, the so-developed image on receptor plate R is fixed" on the fly" as it passes flash fixer unit FF. Unit FF includes lamps, the fixing energy of which is controlled to be so intense, yet so brief in energization (automatically synchronized with plate passage) as to require no interrruption in plate advancement, given an appropriately large advantage in toner fusing speed over plate-advancement speed.

Lastly, imaging plate R is further advanced to a terminal position where it is presented through an ejector slot 8 at Eject Station IV. l-Iere, according to a single plate treatment feature, the advancement mechanism is automatically stopped and left engaged with plate R partly emergent from the eject slot 8 to automatically bar initiation of the next plate-development cycle (of position switch) and also for withdrawal by the machine operator. Pawl P, etc. will thus prevent accidental push-back" and re-engagement of the plate with any advance mechanism and consequent inconvenience and risk of damage. Withdrawal of the port-' ejected plate automatically enables the next development cycle.

According to the described embodiment, receptor film 133 is made manually removable from the adhesive hold-down layer 131 (on anode substrate 123), as indicated by the peeling-back of a corner of 133 in FIG. 3 at station IV. The operator thus may strip-off film 133 and store the anode substrate in bin 71. The foregoing treatment cycle will serve both to introduce and to summarize the salient functions of the machine embodiment, as a preliminary to the detailed description to follow. The foregoing should also provide a frame of reference for the following more particular description of machine elements, so they may be better understood in relation to the entire, integral machine organization. The Timing Chart of FIG. 23 also offers a summary, coordinated picture of machine functions and associated controls, and should be consulted in conjunction with the detailed description. 

1. Apparatus for automatically developing and fixing a latent electrostatic image carried on a rigid imaging plate having a high degree of flatness at least across an image-carrying portion thereof, said imaging plate constituting a portion of a cassette held in an assembled condition by a surrounding packaging envelope, comprising: a transport path along which said imaging plate is unidirectionally moved; an entry station including means for manually injecting an exposed ionographic cassette and moving it to the transport path, and envelope piercing and slitting means for automatically disassembling the cassette during said movement to separate the imaging plate therefrom whereby as the cassette is moved toward the transport path the envelope is progressively slit to free the assembled components of the cassette; a development station including means for bringing the imaging plate into sealing engagement with a development chamber wherein the electrostatic image is contacted by a cloud of toner particles thereby to form a visible image on the plate; a fixing station comprising means for fixing the image-defining toner particles on the plate; an exit station including means for delivering the imaging plate carrying a developed and fixed image thereon; and conveyor means for progressively advancing the imaging plate along the transport path from the entry station to the development station past the fixing station and to the exit station and for effecting a dwell period of predetermined duration of the imaging plate at the development station, all without adversely effecting the image-carrying portion or bending or distorting the flat imaging plate.
 2. Apparatus as set forth in claim 1 wherein the disassembling means includes means for spatially separatiNg the imaging plate from the balance of the cassette along an axis generally perpendicular to the plane of the imaging plate.
 3. Apparatus as set forth in claim 2 wherein the entry station includes a drawer for deposit of the exposed cassette for subsequent sliding movement in a direction substantially lateral to and generally coplanar with that of said transport path.
 4. Apparatus as set forth in claim 3 which further includes means responsive to the completion of sliding movement of the drawer for initiating action of the conveyor means whereby the separated imaging plate is advanced at a substantially constant velocity to the development station.
 5. Apparatus as set forth in claim 4 in which the entry station further includes means for receiving and temporarily storing remaining portions of each cassette after disassembly thereof.
 6. Apparatus as set forth in claim 1 in which said entry station includes additional means for further slitting the envelope and separating it from the imaging plate.
 7. Apparatus as set forth in claim 1 in which the envelope slitting means at the entry station includes lateral cutting means adapted to sever the envelope along the sides of the cassette.
 8. Apparatus as set forth in claim 7 in which said cutting means includes stop means biased in a direction to permit movement of the cassette toward said transport path but prevent retractive movement relative thereto.
 9. Apparatus as set forth in claim 1 wherein the transport means comprises an endless conveyor having one reach thereof extending the length of the tranport path and carrying a plurality of spaced means for engaging and advancing an imaging plate along the transport path.
 10. Apparatus as set forth in claim 1 which includes means responsive to the imaging plate arriving at the development station to effect relative movement of the imaging plate and the chamber in a direction perpendicular to the plane of the plate so that one surface of the imaging plate carrying the latent electrostatic image thereon is exposed to a cloud of toner particles within the chamber during a portion of the dwell period.
 11. Apparatus as set forth in claim 10 wherein the means for effecting sealing engagement of the imaging plate with the chamber is an elevator which lowers the imaging plate from the transport path into engagement with the chamber and thereafter raises the imaging plate back to the plane of the transport path.
 12. Apparatus as set forth in claim 11 wherein the development station includes means for clearing the chamber of the cloud of toner particles prior to raising the imaging plate from the chamber.
 13. Apparatus as set forth in claim 1 wherein the fixing station includes means for fusing the image-defining toner particles on the imaging plate while it is moved along the transport path at substantially constant velocity.
 14. Apparatus as set forth in claim 1 wherein the exit station includes an exit port at which the imaging plate bearing the developed and fixed image is presented for removal, and means responsive to such removal to enable the apparatus to be operated for a subsequent cycle of operation.
 15. Apparatus as set forth in claim 1 wherein the cassette includes a photoemissive electrode portion in parallel spaced relationship to the imaging plate and the imaging plate includes a dielectric receptor sheet carrying the image, said receptor sheet being conveniently strippable from the balance of the imaging plate. 